Our Take: Genetic testing on newborns

In the News: (CNN) Every baby born in the United States is given a routine blood test to screen for dozens of inherited medical conditions. Now, the U.S. National Institutes of Health is exploring whether to use DNA sequencing to screen newborn babies for additional genetic abnormalities and disorders. Such DNA testing would likely complement, but not replace, the current routine blood tests.

Our Take: Julie Horsting, M.R., M.S., LCGC, Beacon Medical Group genetic counselor with Maternal Fetal Medicine, weighs in on this topic.

“The goal of newborn screening has always been to help keep babies as healthy as possible. A small sample of blood is taken from a baby’s heel shorty after birth to test for certain genetic conditions that we know can improve with early detection and treatment. These include conditions like cystic fibrosis, sickle cell anemia, metabolic disorders, and others. While these conditions are genetic, they are often difficult to predict based on family history; most babies identified by newborn screening are the first ones in the family to have the disease.

“Currently, the list of conditions that we test for is limited by several factors: Is the condition severe? Is it treatable? Can we reliably detect it with our technology? Can we predict whether or not someone will develop symptoms with our knowledge of genetics?

“There are many severe genetic conditions that we don’t test for simply because we don’t have the technology needed to reliably detect it. These families sometimes don’t get a diagnosis until it is too late to prevent health problems for their child. With newborn genetic testing we could look for more genetic conditions so that we can identify babies with severe genetic conditions earlier, hopefully before they even have symptoms, and get families connected with the right doctors, the right treatment, and the right support.

“The CNN article touches on several ethical considerations:

“Who gets to make the decision about this genetic testing for a newborn? When we talk about genetic testing, which has implications for one’s genetic relatives, we always want to make sure there is informed consent. Informed consent means the person getting the test understands the possible results and their implications, for themselves and others. Parents make many informed decisions for a newborn right now. Should genetic testing be another one?

“I think this question comes back to the first factor we’ve used in the past to guide newborn screening. If we are using genetic testing to look for a severe disorder that needs treatment right away, that makes sense for a parent to decide for their infant. If we instead consider an adult onset disorder that is mild, that is something we should leave to each individual to decide whether or not they would want to know about it at age 18.

“While this technology holds a lot of promise, the last piece of the puzzle is whether we can predict if someone will develop symptoms given our knowledge of genetics. Some genetic conditions are very straight forward: If you have a ‘spelling error’ in your genetic instructions, you will have symptoms of the disease. Others are more complex: two or more genetic changes are required before someone will have symptoms. Still others are a product of both our genes and our environment. That is why this genetic newborn screening wouldn’t be able to predict someone’s entire future health, nor should we necessarily try to.

“These are big questions, and ones we need to take the time to answer thoroughly. It is important to remember that full genome sequencing of all newborns is not feasible right now; our technology is improving, but the infrastructure isn’t there yet. We have time to consider the best way to responsibly use these advances. It does hold promise, however, to help our tiniest patients who are born with severe, but treatable conditions, get the best care as soon as possible.”